Drilling system and method of using same

ABSTRACT

A drilling system having retractable wings and method of using same. The system includes at least one wing, which can extend from the system once it engages in a casing and abuts against an abutment ring at the bottom end of the casing. When the system starts drilling a hole into the ground, the casing is installed down the hole. In one configuration, the at least one wing is at least partially retracted into the drilling system and locked in this position. In another configuration, the at least one wing extends from the drilling system and locks into an extended position. The system can be connected to a down-the-hole hammer, a top-hammer drilling rod, or any other suitable rock drilling tool/apparatus, and can be used with a single and a dual rotary drilling tool/apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This international patent application claims priority from U.S.Provisional Patent Application No. 62/536,201 filed on Jul. 24, 2017,the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure generally relates to drilling holes in theground, and more particularly to drilling systems, apparatus, and methodof using same for drilling holes in the ground.

BACKGROUND

Ground drilling has been performed for decades, and apparatus, systems,devices, and means for performing such drilling have progressivelyevolved. Ground drilling systems find a use in many fields. Forinstance, ground drilling is used for installing geothermal systemscasing; fluid (e.g. water) conduits; underground casings; rock or groundanchors for stabilizing or solidifying structures and buildings; drilledpiles and micro-piles; and industrial wells for exploiting undergroundnatural resources (e.g. natural gas, petroleum). Many types of systemsand methods adapted for each of these different purposes exist in theindustry.

As noted above, one aspect of performing ground drilling is to installcasing or piping in the ground, for a number of reasons. A particulartechnique used in ground drilling is often referred to as casingdrilling (also called down-the-hole drilling and/or overburden drillingand/or overburden casing systems, and/or casing advancement system). Thesystems used for performing this type of drilling operation areconfigured generally to generate repetitive impacts (percussive systems)together with rotary action for crushing and drilling the ground as thedrill guide device is driven down the hole. In short, the operationallows drilling a hole in rock, overburden, or other types of ground,and simultaneously driving down a casing (or piping) as the hole isbeing drilled. After drilling the hole, the entire drilling system canbe pulled out of the hole, hence leaving in place the casing. Thistechnique substantially increases time efficiency (and thus reducesoperation costs) since both the hole drilling and casing placement areperformed in one single operation.

Existing systems for performing ground drilling have deficiencies, whichthe present invention aims to address at least in part.

SUMMARY

According to various aspects of this disclosure, there is provided adrilling system for drilling a hole into the ground, while installing acasing down the hole. The drilling system is an expandable drillingsystem that can drill various bore sizes and that can be operated with asingle and a dual rotary drilling apparatus. The drilling system can beused as a drilling device for drilling inside a casing, outside a casingor without a casing. The drilling system can be used as a drill bit andcan transform into an under reamer during its operation. The drillingsystem can adapt to various types of ground, including rock, overburdenor a combination thereof. The drilling system comprises few moveableparts and can easily be dismantled to replace parts or for maintenancepurposes.

For example, in accordance with an aspect of this disclosure, there isprovided a drilling system that comprises a driver, a guide devicecomprising at least one retractable wing and a retention system forretaining the driver in the guide device. The driver being movablegenerally along a longitudinal axis of the drilling system between afirst axial position wherein the at least one wing is in a retractedposition and a second axial position wherein the at least one wing is inan extended position. The driver in the first axial position ismechanically lockable, so that the at least one wing is constrained inthe retracted position.

In accordance with another aspect of this disclosure, there is provideda drilling system that comprises a driver, a guide device comprising atleast one wing pivotally retractable, a retention system for retainingthe driver in the guide device, and a locking mechanism for locking theat least one wing in a retracted position or an extended position.

In accordance with another aspect of this disclosure, there is provideda set of wings for a drilling system. The set of wings comprises atleast one wing, the at least one wing comprising a pair of pivotnipples. The drilling system comprises a driver and a guide device, theguide device being configured to receive the pair of pivot nipples ofeach of the at least one wing of the set of wings.

In accordance with another aspect of this disclosure, there is provideda method for using a drilling system in accordance with the presentdisclosure.

In accordance with another aspect of this disclosure, there is provideda drilling system to drill a hole in the ground. The drilling systemcomprises: a first member; a second member; and a retention system. Theretention system comprises a connection to connect the first member andthe second member, the connection comprising a first locked positionwherein the retention system retains the first member and the secondmember from substantially moving relative to one another in axialdirections of the drilling system and in a first rotational direction ofthe drilling system, and wherein the first member and the second membercan move relative to one another in a second rotational direction of thedrilling system to disengage from the first locked position

In accordance with another aspect of this disclosure, there is provideda drilling system to drill a hole in the ground. The drilling systemcomprises: a first member; a second member; and a retention system. Theretention system comprises a connection to connect the first member andthe second member, the connection comprising a locked position whereinthe retention system retains the first member and the second member fromsubstantially moving relative to one another in axial directions of thedrilling system and in a first rotational direction of the drillingsystem, and wherein the first member and the second member can moverelative to one another in a second rotational direction of the drillingsystem to disengage from the locked position. The drilling systemcomprises a retractable wing.

In accordance with another aspect of this disclosure, there is provideda drilling system to drill a hole in the ground. The drilling systemcomprises: a driver for connection to a drilling rod configured toimpart drilling action to the driver; a guide device; at least one wingmounted to the guide device, the at least one wing capable to acquire anextended position to configure the drilling system to drill an extendeddiameter bore and a retracted position to configure the drilling systemto drill a reduced diameter bore; the driver configured to engage theguide device in a selected one of plurality of engagement positions,including a first engagement position in which the at least one wing isin the extended position and a second engagement position in which theat least one wing is in the retracted position; in either one of thefirst and second engagement positions the driver configured tocommunicate the drilling action imparted by the drilling rod to theguide device to drill a bore of a selected one of the extended orretracted diameter.

These and other aspects of this disclosure will now become apparent tothose of ordinary skill in the art upon review of the followingdescription of embodiments in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of non-limiting examples of implementation of thepresent invention is provided hereinbelow with reference to thefollowing drawings, in which:

FIG. 1 shows an exploded view of an example of implementation of thedrilling system according to the invention;

FIG. 2 is a perspective view of the drilling system shown in FIG. 1,shown in a first configuration in which the wings are retracted in orderto drill a small diameter hole;

FIG. 3 is a perspective view of the drilling system shown in FIG. 1,shown in a second configuration in which the wings are expanded to drilla large diameter hole;

FIG. 4 is a perspective view from the top of a driver of the drillingsystem shown in FIG. 1;

FIG. 5 is a side elevational view of the driver of FIG. 4;

FIG. 6 is a side elevational view of the driver of FIG. 4 but in adifferent angular orientation than the one of FIG. 5;

FIG. 7 is a bottom elevational view of the driver of FIGS. 4, 5 and 6;

FIG. 8 is a cross-sectional view of the driver of FIGS. 4 to 7, shownengaged in a guide device, the cross-section being taken in a horizontalplane which is perpendicular to the longitudinal axis of the driver, andFIG. 8 illustrates the retention system for securing the driver to theguide device which comprises a series of retaining pins;

FIG. 9 is a top elevational view of the driver and guide device assemblyof the drilling system shown in FIG. 1, the view being partly cut awayto illustrate certain construction details, the driver being shown in aconfiguration in which the wings are retracted and unlocked;

FIG. 10 is a sectional view taken along lines B-B in FIG. 9;

FIG. 11 is a top elevational view of the driver and guide deviceassembly of the drilling system shown in FIG. 1, the view being partlycut away to illustrate certain construction details, the driver beingshown in a configuration in which the wings are retracted and locked;

FIG. 12 is a sectional view taken along lines A-A in FIG. 11;

FIG. 13 is a top elevational view of the driver and guide deviceassembly of the drilling system shown in FIG. 1, the view being partlycut away to illustrate certain construction details, the driver beingshown in a configuration in which the wings are extended and unlocked;

FIG. 14 is a sectional view taken along lines D-D in FIG. 13;

FIG. 15 is a top elevational view of the driver and guide deviceassembly of the drilling system shown in FIG. 1, the view being partlycut away to illustrate certain construction details, the driver beingshown in a configuration in which the wings are extended and locked;

FIG. 16 is a sectional view of the driver and guide device assemblytaken along lines C-C in FIG. 15;

FIG. 17 is a perspective view of the guide device of the drilling systemshown in FIG. 1;

FIG. 18 is a side elevational view of the guide device shown in FIG. 17;

FIG. 19 is a sectional view of the guide device shown in FIG. 17 takenalong lines 18-18 in FIG. 18;

FIG. 20 is a top plan view of the guide device shown in FIG. 17;

FIG. 21 is a bottom plan view of the guide device shown in FIG. 17;

FIG. 22 is a perspective view of the driver and guide device assembly ofthe drilling system shown in FIG. 1, the view being partly cut away toshow locking features of the driver allowing to lock the driver to theguide device in an axial position;

FIG. 23 is a perspective view of the driver and guide device assembly ofthe drilling system shown in FIG. 1, the view being partly cut away toshow locking features of the driver allowing to lock the driver to theguide device in an axial position different from the position shown inFIG. 22;

FIG. 24 is a perspective view of the guide device shown in FIG. 17, theview being partly cut away to illustrate locking features on the guidedevice which cooperate with the locking features on the driver of thedrilling system shown in FIG. 1;

FIG. 25 is a perspective view of the driver shown in FIG. 4, the guidedevice being omitted;

FIG. 26 is a perspective view of an example of implementation of a wingaccording to the present invention;

FIG. 27 is a side elevational view of the wing shown in FIG. 26;

FIG. 28 is a front elevational view of the wing shown in FIG. 26;

FIG. 29 is a sectional view of the drilling system shown in FIG. 1,shown within a casing, the wings of the drilling system being in aretracted position, the section being taken along the longitudinal axisof the drilling system;

FIG. 30 is a sectional view of the drilling system shown in FIG. 29, thedrilling system extending partially outside the casing and abuttingagainst an abutment ring installed at a bottom end of the casing;

FIG. 31 is a sectional view of the drilling system as shown in FIG. 30,showing the wings of the drilling system in an extended position;

FIG. 32 is a top plan view of the drilling system shown in FIGS. 1 to 3;

FIG. 33 is a perspective view from the bottom of the drilling system,the view being partly cut away along lines H-H in FIG. 32 to illustratethe cooperation between the driver, the guide device and the wings,shown in a configuration in which the wings are in a retracted positionand unlocked;

FIG. 34 is a top plan view of the drilling system shown in FIGS. 1 to 3,the view being partly cut away to show features of the driver and theguide device of the drilling system;

FIG. 35 is a perspective view from the bottom of the drilling system ofFIG. 1, the view being partly cut away along lines G-G in FIG. 34 toillustrate the cooperation between the driver, the guide and the wings,shown in a configuration in which the wings are locked in a retractedposition;

FIG. 36 illustrates a retaining pin of an example of implementation ofthe retention system for securing the driver to the guide device of thedrilling system of FIG. 1;

FIG. 37 illustrates an example of implementation of mechanical fastenersfor securing the retaining pin shown in FIG. 36 for securing the driverto the guide device;

FIG. 38 is a partial sectional view of the guide device shown in FIG.17, showing an inner portion of the guide device which receives a wing;

FIG. 39 shows an exploded view of another example of implementation ofthe drilling system according to the invention;

FIG. 40 shows a side elevational view of the drilling system shown inFIG. 39, shown in a configuration in which wings are expanded to drill alarge diameter hole;

FIG. 41 shows a perspective view of the guide device of the drillingsystem shown in

FIG. 39;

FIG. 42 shows a perspective view of a driver of the drilling systemshown in FIG. 39;

FIG. 43 shows a side elevational view of the driver of the drillingsystem shown in

FIG. 39;

FIG. 44 shows a perspective view of a another example of implementationof a wing according to the present invention, as shown in the drillingsystem of FIG. 39;

FIG. 45 shows a side elevational view of the wing shown in FIG. 44;

FIG. 46 shows a front elevational view of the wing shown in FIG. 44;

FIG. 47 shows a perspective view of the drilling system shown in FIG.39, the view being partly cut away to show features of the driver, theguide device and the wings of the drilling system, which is shown in aconfiguration in which the wings are locked in a retracted position;

FIG. 48 shows a sectional view of the drilling system taken along lineX-X of FIG. 47;

FIG. 49 shows a perspective view of the drilling system shown in FIG.39, the view being partly cut away to show features of the driver, theguide device and the wings of the drilling system, which is shown in aconfiguration in which the wings are in a retracted position andunlocked;

FIG. 50 shows a sectional view of the drilling system taken along lineX-X of FIG. 49;

FIG. 51 shows a perspective view of the drilling system shown in FIG.39, the view being partly cut away to show features of the driver, theguide device and the wings of the drilling system, which is shown in aconfiguration in which the wings are in an extended position andunlocked;

FIG. 52 shows a sectional view of the drilling system taken along lineX-X of FIG. 51;

FIG. 53 shows a perspective view of the drilling system shown in FIG.39, the view being partly cut away to show features of the driver, theguide device and the wings of the drilling system, which is shown in aconfiguration in which the wings are locked in an extended position;

FIG. 54 shows a sectional view of the drilling system taken along lineX-X of FIG. 53;

FIG. 55 shows a sectional view of the drilling system shown in FIG. 39,shown within a casing, the wings of the drilling system being in aretracted position and locked, the section being taken along thelongitudinal axis of the drilling system, the drilling system beingconfigured to drill inside the casing;

FIG. 56 shows a sectional view of the drilling system shown in FIG. 39,shown within a casing, the wings of the drilling system being in anextended position and locked, the section being taken along thelongitudinal axis of the drilling system, the drilling system beingconfigured to drill a large diameter hole, for instance to install acasing;

FIG. 57 shows a perspective view of an example of an abutment ring formounting on a casing;

FIG. 58 shows a perspective view of an example of a casing crownmountable on a bottom end of a casing; and

FIG. 59 shows a sectional view of the drilling system shown in FIG. 39,shown within a casing, the wings of the drilling system being in aretracted position and locked, the section being taken along thelongitudinal axis of the drilling system, and a casing crown as shown inFIG. 58 being mounted to the bottom end of the casing.

In the drawings, embodiments of the invention are illustrated by way ofexample. It is to be expressly understood that the description anddrawings are only for purposes of illustration and as an aid tounderstanding, and are not intended to be a definition of the limits ofthe invention.

DETAILED DESCRIPTION OF EMBODIMENTS

To facilitate the description, any reference numeral designating anelement in one figure will designate the same element if used in anyother figure. In describing the embodiments, specific terminology isused but the invention is not intended to be limited to the specificterms so selected.

The present invention pertains to a drilling system which can be usednotably with DTH (down the hole) hammer or top hammer drilling rod knownin the art. A detailed description of the structure and operation of aDTH hammer or top hammer drilling rod is not necessary for understandingthe present invention. Suffice it to say that the drilling rod iscapable of hammering action, which is imparted to the drilling system inorder to produce a hole by breaking rock or other material. The drillingrod is also capable of rotation, which in combination with the hammeringaction indexes the drilling system to progressively disintegrate therock. Finally, the drilling rod can also be longitudinally displaced inorder to advance or retract the drilling system in the hole beingdrilled.

The drilling system of the present invention may be used to drill down ahole in the ground and install a casing in the hole. After drilling thehole and installing the casing in said hole, the drilling system can bepulled out of the hole, leaving the casing in place. In a broad exampleof implementation, this technique can be implemented with the drillingsystem of the present invention in the following manner. The drillingsystem may be engaged in a casing which will be driven down a hole.While the drilling system is displacing within said casing, the boresize of the drilling system is smaller than an interior diameter of saidcasing. After the drilling system reaches a bottom end of said casing,the bore size of the drilling system can be selectively and momentarilyexpanded such that the bore size may become slightly larger than anexterior diameter of said casing. Thus, as the drilling systemprogressively drills a hole, said casing may be driven down the hole.

FIGS. 1 to 3 show an example of a drilling system 1 in accordance withan embodiment of the present invention. In this embodiment, the drillingsystem 1 includes a driver 100 which is configured so as to connect atan upper end 2 thereof to a DTH hammer (not shown) or any other suitablerock drilling tool/apparatus (e.g., a drilling rod); a guide device 200which is configured for receiving/engaging the driver 100; at least onewing 300 configured for engaging the guide device 200; and a retentionsystem 400 for retaining the driver 100 into the guide device 200 oncethe driver 100 is engaged therein. In this example, the drilling system1 includes three wings 300 configured for pivotally engaging the guidedevice 200 and the retention system 400 includes three retaining pins401 for retaining the driver 100 into the guide device 200. In othervariants, the reader will readily understand that the retention system400 may include any number of retaining pins 401 and/or any othersuitable retention components. Also, in other variants, the drillingsystem 1 may include any number of wings 300. As further discussed laterwith more details, in one example of operation, the drilling system 1may be used for drilling a hole and simultaneously driving down a casingin the hole.

The configuration of the driver 100 in accordance with the presentinvention may take any suitable form. Different aspects of an example ofimplementation of the driver 100 in accordance with the presentinvention and interactions between the driver 100 and other parts of thedrilling system 1 shown in FIGS. 1 to 3 will now be described. Moredetails specific to other parts of a drilling system 1 in accordancewith the present invention will be discussed later.

The driver 100 may have a generally circular geometry including diametervariations, protrusions, and grooves or slots machined on its outersurface. FIGS. 4 to 7 show an example of the driver 100 in accordancewith the present invention. In this embodiment, the driver 100 has anupper section 101, which connects to a DTH hammer or top hammer drillrod (not shown), and a lower section 102, which engages the guide device200. The upper section 101 includes a series of splines which allow theDTH hammer to impart rotational motion to the driver 100 and also allowa limited range of axial movement between the driver 100 and the DTHhammer to permit the hammering action.

The driver 100 includes a bayonet connection at the upper portion of thelower section 102. The bayonet connection allows connecting the driver100 with the guide device 200 as a result of the driver 100 being pushedinto the guide device 200 and then twisted to lock the driver 100 to theguide device 200. The bayonet connection includes inter-fitting featureson both the driver 100 and the guide device 200, which mate with oneanother to allow the connection to be realized. On the driver 100 thebayonet connection includes at least one recessed portion 128 that hastwo vertically spaced apart slots 126 and 127, defined between arcuateprojections 129, 131, each shaped as a segment of a circle. The freeextremities of the projections 129 and 131 have camming surfaces 133,135 to facilitate engagement with the corresponding features in theguide device 200. Alternatively or additionally, in other embodiments,the at least one recessed portion 128 may include more than twovertically spaced apart slots.

The bayonet connection is configured to allow the driver 100 to belocked to the guide device 200 in two different axial positions. In afirst of those positions, the driver 100 projects further from the guidedevice 200 than in the second position. That is, in the second position,the driver 100 is positioned deeper within the guide device 200 than inthe first position. The two locking positions are achievable as a resultof the presence of multiple slots in the driver 200, which define two,or possibly more engagement options. For instance, in some embodiments,the bayonet connection may be configured to allow the driver 100 to belocked to the guide device 200 in more than two different axialpositions. A particular engagement option can be achieved by positioningthe driver 100 in a selected axial position with relation to the guidedevice 200 and then performing a twisting movement to lock thecomponents together.

Since an axial movement is necessary between the driver 100 and theguide device 200 to achieve the desired engagement option, a retentionsystem is provided in order to avoid the driver 100 from being fullypulled out of the guide device 200. The retention system is designed toallow a range of axial movement between the driver 100 and the guidedevice 200 that is sufficient to permit two or more engagement options.However, the retention system does not allow the driver 100 to axiallymove with relation to the guide device 200 outside of the range ofmovement. A practical advantage is to design the retention system suchthat the end most engagement option generally coincides with the end oftravel allowed by the retention system. This allows the operator toremotely displace the driver 100 axially until it abuts the end oftravel position, where the slots and corresponding projections are inalignment with each other. A twisting motion then suffices to mesh theslots and the projections.

The axial movement between the driver 100 and the guide device 200permits to actuate the wings 300 engaged in the guide device 200, suchthat the wings 300 can progressively move between a retracted positionand an extended position (or vice versa). The axial movement of thedriver 100 relative to the guide 200 in both a downward and an upwarddirection allows to control the movement of the wings 300. For instance,in this embodiment, upon axially moving the driver 100 downwardly (i.e.deeper) within the guide device 200, the wings 300 progressively spreadout of the guide device 200 to increase the total bore size of thedrilling system 1. Upon axially moving the driver 100 upwardly withinthe guide device 200, the wings 300 may progressively retract inside theguide device 200. In this embodiment, the wings 300 progressively pivotbetween a retracted position and an extended position (or vice versa),such that when the wings 300 are in an extended position, the total boresize of the drilling system 1 is increased, and when the wings 300 arein a retracted position, the total bore size of the drilling system 1 isdecreased. In other embodiments, the wings 300 may extend and retractfrom the guide device 200 with a motion that is other than a pivotalmotion, such as translational motion.

A practical advantage of a drilling system 1 capable of adoptingdifferent bore sizes, for instance two or more different bore sizes, isthat it may allow to vary the inner diameter of a hole along alongitudinal direction thereof and/or it may allow to drill consecutiveholes with different diameters, thus providing greater flexibility inuse. Additionally or alternatively, a drilling system 1 capable ofhaving various bore sizes may, for instance, engage a restricted space(e.g. tunnel, hole, piping, tubing, casing, or other restrictedpassages), and then expand/deploy for increasing its total bore sizewhen the restricted space has been cleared. A practical example ofoperation of the drilling system 1 implementing the above principle willbe described later.

To achieve such control of the pivotal movement of the wings 300, alower portion of the lower section 102 of the driver 100 is configuredto slidably cooperate with the wings 300. More particularly, the driver100 includes an enlargement 104 at the lower portion of the lowersection 102 that includes a guiding surface 125 configured to slidinglyengage a rear surface 350 of the wings 300. The guiding surface 125 hasa cam profile defining a spherical geometry. In this embodiment, theguiding surface 125 extends longitudinally along the longitudinal axisX-X of the driver 100 and tapers toward the centerline at the lowerextremity of the enlargement 104, such that the diameter of theenlargement 104 decreases progressively towards the bottom end 103 ofthe driver 100. By axially moving the driver 100 within the guide device200, the guiding surface 125 slidingly engages the rear surface 350 ofthe wings 300, as will be illustrated in following figures. Since theguiding surface 125 tapers, when the enlargement 104 moves downwardly,i.e. towards the bottom end of the guide device 200, the guiding surface125 engages and progressively drives the wings 300 out through apertures250 in the guide device 200. When the enlargement 104 moves upwardly,i.e. towards the upper end of the guide device 200, the enlargement 104moves out of engagement with the wings 300, allowing the wings 300 toretract inside the apertures 250 of the guide device 200.

The drilling system 1 may be selectively configured to drill a hole inone or more drilling configurations. In this embodiment, in a firstdrilling configuration, the wings 300 are pivotally retracted in theguide device 200 as a result of the driver 100 being positioned in thefirst axial position. In a second drilling configuration, the wings 300are pivotally extended from the guide device 200 as a result of thedriver 100 being positioned in the second axial position within theguide device 200.

The drilling system 1 may also be configured to lock the wings 300 in anextended position and/or in a retracted position. A practical advantageof being able to lock the wings 300 in a retracted position is, notably,that it allows the drilling system 1 to rotate while longitudinallydisplacing within a casing in order to clean the interior of saidcasing, or for any other purposes, without risking to jam the wings 300in the interior of said casing, for instance as a result of the wings300 deploying due to centrifugal force or mechanical engagement whilethe drilling system 1 resides within and/or passes through the casing.Also, a practical advantage of being able to lock the wings 300 in anextended position is, notably, that the drilling system 1 may be used topull a casing out from a hole having been drilled. These two differentaxial positions will be further described later and illustrated infollowing figures.

The driver 100 includes, at a lowermost portion of the lower section 102(i.e. proximate a lower end 103 of the driver 100), radial projections130 configured to interact with a notch 340 formed at an inner surface320 of each of the wings 300, all of which defining a locking mechanismfor locking the wings 300 in the retracted position. The radialprojections 130 include a camming surface 132 to facilitate rotatableengagement of a radial projection 130 in a notch 340 of a wing 300. Inthis embodiment, the locking mechanism on the driver 100 includes threeradial projections 130, each of which being configured to register in acorresponding notch 340 on each one of the three wings 300. It is to beunderstood that in other embodiments where there may be more than orless than three wings 300, the wing retaining mechanism on the driver100 may include more than or less than three radial projections 130,each of which for interacting with a corresponding wing 300. Theoperation of the locking mechanism will be described in more detailslater.

FIG. 8 illustrates a cross-section of an example of a drilling system 1according to the present invention. The cross-section is being taken ina horizontal plane intersecting perpendicularly the longitudinal axisX-X of the driver 100 at a middle portion of the lower section 102. Thecross-section plane intersects horizontally an upper portion of thelower section 220 of the guide device 200, and shows how the driver 100is secured within the guide device 200 by the retaining system 400.

The retaining system 400 can be implemented in more than one way. Inthis embodiment, the retaining system 400 resides at the upper portionof the lower section 220 of the guide device 200 and includes retainingpins 401 inserted in holes 260 in a slide-fit fashion. The retainingpins 401 are secured in holes 260 by mechanical fasteners, for instanceby circlips 800, such that the percussions or impacts imparted by thehammering action of the DTH or top hammer to the drilling system may notaccidentally dislodge the retaining pins 401 from the holes 260. Inother variants, the retaining pins 401 may also be inserted in holes 260in a press-fit fashion without the need of mechanical fasteners tosecure the retaining pins 401 in holes 260. The holes 260 are orientedin directions perpendicular to a longitudinal axis Y-Y of the guidedevice 200 (but not intersecting the longitudinal axis) and located onthe periphery of the guide device 200. In this example, the retainingpins 401 lay in the same horizontal plane, i.e. they are coplanar (asillustrated in FIG. 8). The retaining pins 401 are configured such thattheir respective longitudinal axes Z1, Z2, Z3 generally intersect at theperiphery of the guide device 200. In this embodiment, the threeretaining pins 401 form the edges of a triangle (the exact geometricalshape does not impact how the retaining system 400 may work; this issimply for the reader to better understand what is represented on FIG.6). In other embodiments, for instance, where there may be fourretaining pins 401, the retaining pins 401 form the edges of a square(instead of a triangle as described above). Yet in other variants, theretaining system 400 can be implemented in any other suitable manner(i.e. not necessarily implemented with retaining pins 401).

In this embodiment, the middle portion of the lower section 102 of thedriver 100 includes a constricted area 120 (i.e. an area having asmaller diameter than the lower and upper adjacent portions thereof)having a circumferential surface 121 delimited by an upper end-of-travelabutment 122 and a lower end-of-travel abutment 123 (as best shown inFIGS. 4 to 6). In this embodiment, the surface 121 of the constrictedarea 120 is configured to be in slidable interaction with thecircumference of the retaining pins 401 distributed about theconstricted area 120 when the driver 100 axially moves with relation tothe guide device 200 between the first axial position (described above)and the second axial position (described above), where the driver 100 isengaged deeper within the guide device 200. In this embodiment, theretaining pins 401 generally engage the abutment 123 about theconstricted area 120 when the driver 100 is in the first axial position,and the constricted area 120 is configured such that the retaining pins401 generally engage the abutment 122 when the driver 100 is in thesecond axial position.

FIGS. 2, and 9 to 12 illustrate an example of a first drillingconfiguration and show how the guiding surface 125 of the enlargement104 abuts against the wings 300, hence interacts with the wings 300 whenthe driver 100 is positioned within the guide device 200 in the firstaxial position, and how the locking mechanism for locking the wings 300in the retracted position prevents the wings 300 from extendingoutwardly from the guide device 200 when the driver 100 and the guidedevice 200 lock in the first locking position. In this embodiment, thedrilling system 1 connected to a DTH hammer or drilling rod (not shown)can drill a hole while wings 300 are arranged in a retracted position,i.e. the wings 300 rest in a completely (or substantially) retractedmanner within corresponding apertures 250 in the guide device 200. Inthis position, the wings 300 are positioned such that the guide device200 is the only part of the drilling system 1 that contacts the groundbeneath while drilling. In this first drilling configuration, the driver100 is in the first axial position and retaining pins 401 of theretention system 400 generally coincide with the lower end-of-travelabutment 123 of the driver 100. In this axial position, if the driver100 twists in a clockwise direction, the slots and the projections ofthe bayonet connection mesh so that the driver 100 and the guide device200 are locked against a relative angular and axial movement, in a firstlocking position. In this locking position, the lower extremity of theenlargement 104 generally frees the rear surface 350 of the wings 300,i.e. the guiding surface 125 of the enlargement 104 does not pressagainst the rear surface 350 of the wings 300 resting in the retractedposition. In this first locking position, the locking mechanism forlocking the wings 300 in the retracted position is configured such thateach one of the radial projections 130 respectively rotatably engages anotch 340 formed at an inner surface 320 of each one of wing 300. Byengaging the notch 340 of a respective wing 300, each radial projection130 prevents a pivotal movement of the wing 300, i.e. each wing 300 ismechanically constrained (retained) in its retracted position. In orderto enable the wings 300 to pivot, the driver 100 has to be turned in acounterclockwise direction relative to the guide device 200, to unlockfrom the guide device 200 and disengage the radial projections 130 fromthe notches 340 from the respective wings 300. In other variants, thedrilling system 1, including its driver 100 and guide device 200, may beconfigured such that the driver 100 has to be turned in a clockwisedirection instead of a counterclockwise direction relative to the guidedevice 200 to unlock the driver 100 from the guide device 200.

FIGS. 3 and 13 to 16 illustrate an example of a second drillingconfiguration and illustrate how the guiding surface 125 of theenlargement 104 of the driver 100 interacts with the wing's 300 when thedriver 100 is positioned within the guide device 200 in the second axialposition. In this embodiment, the drilling system 1 can drill a holewhile the wings 300 are in the extended position. The wings 300 extendfrom the apertures 250 at an angle of attack θ relative to thelongitudinal axis Y-Y of the guide device 200. When the wings 300 are inthe extended position, the angle of attack θ of each wing 300 isgenerally the same, as a result of the enlargement 104 being concentricrelative to the rear surface 350 of the wings 300 and thus pushingequally on the rear surface 350 of each wing 300. This may help tobetter balance the drilling system and may provide a balanceddistribution of the drilling forces in the components of the drillingsystem 1. In this embodiment, the angle of attack θ of each wing 300 isaround 30°. In other embodiments, the angle of attack θ may be around20°, around 60°, or any other suitable angle of attack θ. In this seconddrilling configuration, while the wings 300 are in their extendedposition, the slots and the projections of the bayonet connection maymesh so that the driver 100 and the guide device 200 may lock in asecond locking position. The wings 300 are therefore blocked in theirextended position.

If the driver 100 and the guide device 200 disengage from the secondlocking position, axial movement of the driver 100 within the guidedevice 200 is now possible. The driver 100 can thus longitudinally moverelative to the guide device 200 from the second axial position towardsthe first axial position, which in turn allows the wings 300 topivotally retract from their extended position. As will be discussedlater, the wings 300 can retract from their extended position to theirretracted position simply by the effect of gravity or by applying aconcentric force on the wings 300.

The driver 100 includes an open channel 190 extending centrally alongthe longitudinal axis X-X of the driver 100 which constitutes a pathwayfor compressed air (or other fluids and/or mixtures, for instance water,drilling foam, chemical products, or other fluids) towards the bottomend of the drilling system 1 to dislodge clogs or debris.

As shown on FIGS. 17 to 20, the guide device 200 has a generallycircular geometry. It includes an open upper end 205 to receive thedriver 100, an upper section 210 and a lower section 220. The uppersection 210 of the guide device 200 has an outer diameter D1 and thebottom section 220 has an outer diameter D2. The outer diameter D1 ofthe guide device 200 is larger than the outer diameter D2. For instance,in this example, the outer diameter D1 measures no more than 12 inches(no more than 30.5 cm) and the outer diameter D2 measures no more than11 inches (no more than 28 cm). In other embodiments, the diameters D1and D2 may have other dimensions. For instance, in other embodiments,the outer diameter D1 may be identical to the outer diameter D2.

The junction of the upper and bottom sections 210, 220 of the guidedevice 200 forms a shoulder 230. The shoulder 230 includes a chamfer.When the drilling system 1 operates for drilling a hole andsimultaneously driving down a casing in the hole being drilled, theshoulder 230 abuts against an abutment ring 510 mounted to an end of acasing to enable the drilling system 1 to drive down the casing in ahole being drilled.

The shoulder 230 may have any suitable dimension. For instance, in thisembodiment, a thickness S of the shoulder 230 is no more than 0.5 inches(no more than 1.3 cm). In other embodiments, the thickness S is no morethan 0.2 inch (no more than 0.5 cm). The thickness S may vary dependingon the size of the drilling system 1 and/or the size of the DTH hammerused. For instance, in some cases, a ratio of a thickness S over anouter diameter D1 of the guide device 200 is preferably less than 8%. Ifthe shoulder 230 is too thin, the shoulder 230 may wear too quickly dueto friction with an abutment ring 510 (described later) mounted to anend of a casing when the drilling system 1 operates for drilling a holeand simultaneously driving down a casing in the hole being drilled. Ifthe shoulder 230 is too large, the wings 300 may have to extend more(e.g. the angle of attack θ may have to be larger and/or the wings 300may have to be longer) to sufficiently increase the bore size of thedrilling system for being larger than the outer diameter of the casingbeing driven down.

The guide device 200 includes sludge discharging grooves 240 extendinglongitudinally along a length L_(x) of the guide device 200 on its outersurface for ejecting sludge, sands, pebbles, and grindings from thebottom of the borehole while drilling occurs. The guide device 200includes three sludge discharging grooves 240 distributed about theperiphery of the outer surface of the guide device 200. In othervariants, there may be more or less sludge discharging grooves 240,and/or the discharging grooves 240 may be at least partly curved and/orat angle relative to the longitudinal axis Y-Y of the guide device 200of the drilling system 1 instead of being straight.

The apertures 250 for receiving the wings 300 are equally spaced apartand reside circumferentially in the lower section 220 of the guidedevice 200. In other variants, the apertures 250 may not be equallyspaced apart.

FIG. 38 depicts the interior of the guide device 200. In thisembodiment, the guide device 200 includes a pair of slots 280 formingpivot supports 281 for receiving a pair of wing pivot nipples 330 (bestshown in FIGS. 26 to 28). When installing each wing 300 in an aperture250 of the guide device 200, the pair of wing pivot nipples 330 alignswith a pair of slots 280 and slide therein until they generally reachthe closed end (i.e. the extremity) of each slot 280. In this position,the pair of wing pivot nipples 330 may rest in place in the slots 280,such that each wing 300 may be freely supported without additionallybeing secured or fastened to the guide device 200. In this position, thewings can pivot between the retracted position and the extendedposition, as described above. In other embodiments, the interior of theguide device 200, for instance, for receiving wings 300, may beconfigured in any other suitable manner.

FIGS. 22 to 25 illustrate an example of the bayonet connection on theguide device 200 that allows locking the driver 100 to the guide device200. In this embodiment, the bayonet connection on the guide device 200includes a set of two vertically spaced apart arcuate elongatedprojections 212 and 214 at the upper section 210 of the guide device200, each shaped as a segment of a circle. Both extremities of each ofthe elongated projections 212 and 214 have camming surfaces 216 and 218to facilitate engagement with the inter-fitting features of the bayonetconnection located on the driver 100.

FIG. 22 illustrates an example of the drilling system 1 in the firstdrilling configuration as discussed above. As shown, when the driver 100is in the first axial position and twists in a clockwise direction, anelongated projection 212 of the bayonet connection on the guide device200 registers into a slot 127 of the bayonet connection on the driver100. An arcuate projection 131 of the bayonet connection on the driver100 registers between elongated projections 212 and 214 of the bayonetconnection on the guide device 200. In this first drillingconfiguration, the bayonet connection is realized, and thus the driver100 and the guide device 200 are locked against a relative angular andaxial movement. The locking mechanism for locking the wings 300 in theretracted position blocks any further pivotal movement of the wings 300.When the drilling system 1 is drilling in this configuration, a majorityof the impact force provided by the hammering action of the DTH hammerwhile drilling is transmitted to the guide device 200 through the driver100 by an interface between elongated projections 212 and 214 of theguide device 200 and arcuate projections 131 and 133 of the driver 100.

FIG. 23 illustrates an example of the drilling system 1 in the seconddrilling configuration as discussed above. As shown, when the driver 100is in the second axial position and twists in a clockwise direction,elongated projections 212 and 214 of the bayonet connection of the guidedevice 200 register respectively into slots 126 and 127 of the bayonetconnection on the driver 100. In this second drilling configuration, thebayonet connection is realized, and thus the driver 100 and the guidedevice 200 are locked against a relative angular and axial movement,When the drilling system 1 is drilling in this configuration, at least amajority of the impact force provided by the hammering action of the DTHhammer while drilling is transmitted to the guide device 200 through thedriver 100 by an interface between an impact transmission surface 124located beneath arcuate projections 131 and prolonging along acircumference of the driver 100, and a corresponding impact transmissionsurface 224 on the guide device 200 configured for mating with saidimpact transmission surface 124 of the driver 100.

The guide device 200 includes fluid outlet ports 700 traversing thebottom face 270 thereof and fluidly communicating with channel 190 ofthe driver 100, thus allowing compressed air (or other fluids and/ormixtures, for instance water, drilling foam, chemical products)channeled therethrough to be discharged through fluid outlet ports 700.In some variants, there may be outlet ports at other locations at theperiphery of the guide device 200.

The guide device 200 includes inserts 600 mated with a bottom face 270of the guide device 200. The inserts 600 may include carbide buttons, orother types of buttons. The inserts 600 may be positioned on the bottomface 270 (including on an angled edge at the periphery of the bottomface 270), which is the surface of the guide device 200 thatpredominantly contacts the ground beneath when drilling. When worn outor broken, the inserts 600 may be replaced by new sets of inserts 600.

Different aspects and/or additional variants of the wings 300 will nowbe described.

FIGS. 26 to 28 illustrate an example of a wing 300 in accordance withthe present invention. In this embodiment, each wing 300 includes anouter surface 310, an inner surface 320, wing pivot nipples 330, a notch340 formed in the inner surface 320 of the wings 300, a rear surface350, upper surfaces 360, 370 and a bottom surface 380.

Some characteristics of the wings 300 such as the shape, size and/orangle of attack θ, may affect working aspects of the drilling system 1.For instance, the bore size of the drilling system 1 while drilling inthe second drilling configuration (discussed above) can be larger orsmaller, depending on the shape, size and/or angle of attack θ of thewings 300. Alternatively or additionally, the shape, size and/or angleof attack θ of the wings 300 may affect how the wings 300 interacts withother components of the drilling system 1, such as the driver 100 andthe guide device 200, including how the wings 300 interact with thelocking mechanism of the driver 100 and contact the contact area on theguide device 200. Such aspects will be further discussed later withrespect to variants of the drilling system 1.

When the wings 300 are in their extended position and the drillingsystem 1 drills a hole, the bottom surface 380 of the wings 300 strikesthe ground. The bottom surface 380 of the wings 300 includes inserts 600as those described above with respect to the guide device 200.

Returning to FIGS. 9 to 12, when the wings 300 are in their retractedposition, the upper surface 360 of each wing 300 contacts an upper innersurface 251 of the apertures 250.

Returning to FIGS. 13 to 16, when the wings 300 are in their extendedposition, the upper surface 370 of each wing contacts the upper innersurface 251 of apertures 250 and the rear surface of the wings 300contact the enlargement 104. The contact area between upper surface 370of the wings 300 and the upper inner surface 251 of apertures 250 iscritical, in that stress applied on the bottom surface 380 of the wings300 while the drilling system 1 strikes the ground beneath and drills ahole with the wings 300 in the extended position is mostly transferredto the guide device 200 structure at this contact area, such that lessstress (or almost no stress) is applied to wing pivot nipples 330 duringdrilling in this drilling configuration.

Although wings 300 are generally described as being assembled in theguide device 200 and part of the drilling system assembly, wings 300may, for instance, be included in replacement kits provided to operatorsof the drilling system 1.

In order to further describe how each part of the drilling system 1 thathas been described above interacts, concurrently or alternately, anexample of a drilling operation that may be done while using thedrilling system 1 discussed above is described.

FIGS. 29 to 31 illustrate an example of drilling operation with adrilling system 1 in accordance with the present invention, when thedrilling system 1 is used with a single rotary drilling apparatus. Thedrilling system 1 has been primarily assembled, such that the wings 300have been installed in the guide device 200, and the driver 100 has beenaxially engaged in the guide device 200, and secured within the guidedevice 200 by retaining pins 401. Then, the drilling system assembly isconnected to a DTH hammer (not shown) or any suitable device (e.g., adrilling rod) by the upper end 2 of the driver 100. Once the drillingsystem 1 is assembled, the drilling system 1 engages a casing 500 whichwill be driven down a hole to be drilled by operating the drillingsystem 1.

With reference to FIG. 29, the drilling system 1 is engaged at one endof a casing 500. The casing has a generally circular geometry (i.e.cylindrical) and has an inner diameter Dc1 and an outer diameter Dc2.The way an operator of the drilling system 1 engages said drillingsystem 1 in the casing 500 is not necessary to understand how thedrilling system can operate. Suffice to say that the drilling system 1is engaged at one end of the casing 500, which includes an abutment ring510 (also known as an abutment crown), as shown in FIG. 57, mounted(e.g. welded), or integrally part of the casing, at an opposite end ofthe casing 500 (e.g. bottom end of the casing 500). In this embodiment,the shoulder 230 of the guide device 200 may abut against the abutmentring 510 when the drilling system 1 reaches the bottom end of the casing500 and while drilling occurs. In practice, since the shoulder 230 abutsagainst the abutment ring 510 during drilling, the casing 500 can bedriven down the hole by the drilling system 1 as it descends in thehole, i.e. the drilling system 1 drills the hole and drives down thecasing 500 simultaneously in the hole. The friction between the abutmentring 510 and the shoulder 230 imparted by the drilling system 1 beingpushed against the abutment ring 510 may allow the driver 100 and theguide device 200 to lock and unlock from one of the locking positions ofthe bayonet connection. The guide device 200 is thus frictionallymaintained stationary while the driver 100 twists, for instance tounlock from one of the locking positions, inside the guide device 200.

Since the outer diameter D1 of the upper section 210 of the guide deviceis substantially equal to the inner diameter Dc1 of the casing 500, theupper section 220 of the guide device 200 can slidably engage the casing500.

While the drilling system 1 is engaged within the casing 500, as shownin FIG. 29, the drilling system 1 can be arranged in the first drillingconfiguration as described above, such that the drilling system 1 canrotate while longitudinally moving within the casing 500 in order toclean the interior of the casing 500, or for any other purposes, withoutrisking to jam the wings 300 (as a result of the wings 300 deploying dueto centrifugal force or mechanical engagement) in the casing 500.

Once the shoulder 230 of the guide device 200 abuts against the abutmentring 510 at an end of the casing 500 (as shown in FIGS. 30 and 31), asubstantial portion of the bottom section 220 of the guide device 200clears the casing 500, such that wings 300 can then be deployed in theirextended position.

With reference to FIGS. 30 and 31, the drilling system 1 unlocks fromthe first locking position by turning the driver 100 relative to theguide device 200 in a counterclockwise direction, to unlock the bayonetconnection and disengage the locking mechanism of the wings 300. Afterunlocking from the first locking position, the drilling system 1 canmove to the second axial position, and then twists in a clockwisedirection relative to the guide device 200 to lock the bayonetconnection in the second locking position. While the drilling system 1is in the second drilling configuration (as shown in FIG. 30) and thewings 300 are extended, a bore size B of the drilling system 1 isslightly larger than the outer diameter Dc2 of the casing 500.

Where the drilling system 1 is in the second drilling configuration andthe wings 300 are extended, drilling can occur. Once drilling iscompleted, for instance when the casing 500 is completely orsubstantially positioned into the ground, the operator can activate thedrilling rod (not shown) in a counterclockwise direction, so that thedriver 100 turns relative to the guide device 200 and consequentlyunlock from the second locking position. The driver 100 can then axiallymove within the guide device 200 from the second axial position to thefirst axial position. As the driver 100 progressively moves towards thefirst axial position, the guiding surface 125 of the enlargement 104 ofthe driver 100, frees the rear surface 350 of the wings 300, therebyallowing the wings 300 to pivotally retract in the apertures 250. Thewings 300 may generally retract simply by the effect of gravity, forinstance when the hole is being drilled vertically. Alternatively, bypulling the drilling system 1 out from the casing 500, the outer surface310 of the wings 300 may abut against the abutment ring 510, such thatthe wings 300 are biased inwardly by the abutment ring 510 pressingagainst the outer surface 310 of the wings 300.

A practical advantage of having wings 300 that may pivot for retractingand extending from the guide device 200 is that the wings 300 canuneffortlessly retract by themselves (e.g. only by the effect ofgravity), or almost uneffortlessly (e.g. with nominal force applied onthe outer surface of the wings 300 by the abutment crown 510 to bias thewings 300 inwardly to retract). For instance, if desired, afterretracting the wings 300 and while the driver is in the first axialposition, the operator can then activate the drilling rod in a clockwisedirection to turn the driver 100 relative to the guide device 200, whichis still abutting against the abutment ring 510, thereby configuring thedrilling system 1 in the first drilling configuration.

If for any reasons the operator desires to pull the casing 500 out ofthe drilled hole, the drilling system 1, configured in the seconddrilling configuration, can be used for this purpose. In this case,while the drilling system 1 is in the second drilling configuration, thewings 300 are locked in their extended position, and thus by pulling thedrilling system 1 upwardly from the bottom of the hole, the outersurface 310 of the wings 300 may abut against the abutment ring 510,thereby causing the drilling system 1 to pull the casing 500 out of thehole.

The drilling system 1 may also be used with a dual rotary drillingapparatus. The operation of the drilling system 1 with a dual rotarydrilling apparatus is similar to what was discussed above with respectto operation with a single rotary drilling apparatus, but somedifferences are discussed below.

When using the drilling system 1 with a dual rotary drilling apparatus,the casing 500 rotates and serves itself as a device to drill the holewhile drilling concurrently with the drilling system 1 inside the casing500. More particularly, the casing 500 may rotate in thecounterclockwise direction (i.e. the dual rotary drilling apparatus canmake the casing 500 rotate) while the drilling system 1 in the casing500 is drilling in the clockwise direction.

In such case, as shown in FIG. 59, a casing crown 520 is mounted (e.g.welded, screwed or otherwise fastened) at an end of the casing 500 (i.e.at the bottom end of the casing 500). As shown in FIG. 58, the casingcrown 520 comprises a series of projections 522 (e.g. teeth) along itscircumference that may dig into the ground as the casing 500 rotate. Theshape of the casing crown 520 and projections 522 thereof allows thecasing 500 to descend in the ground while the casing crown 520 isdigging into the ground. Also, when operated with a dual rotary drillingapparatus, the casing crown 520 may not limit the relative position ofthe casing 500 and the drilling system 1, as the drilling system 1 maynot abut against the casing crown 520, as opposed to the abutment ring510 discussed above with respect to the operation of the drilling system1 with a single rotary drilling apparatus.

While the casing 500 is descending, it fills up with soil (a soil corebuilds up inside the casing 500). During this operation, the drillingsystem 1 remains inside the casing 500 and drills through the soil (e.g.overburden) filling up the casing 500.

A practical advantage of using the drilling system 1 while drilling ahole and installing the casing 500 this way is that this may help toreduce compressed air (or other fluids and/or mixtures, for instancewater, drilling foam, chemical products) loss in the ground, as thecompressed air used during drilling may remain substantially inside thecasing 500 before being ejected upwardly through the sludge discharginggrooves 240 of the guide device 200 with debris. This may ultimatelyavoid, or at least substantially reduce, a pressure build-up imparted tothe ground due to compressed air (or other fluids) used during drilling.

Once a boulder or rock is hit during drilling, the drilling system 1 maymove forward inside the casing 500 and may drill in the first drillingconfiguration (as discussed above) until the boulder or rock is crushedor the path for the casing 500 is cleared. Alternatively, the casing 500may be pulled up to clear at least the bottom section 220 of the guidedevice 200, such that the wings 300 can be deployed in their extendedposition, thereby allowing the drilling system 1 to drill in the seconddrilling configuration (as discussed above).

In this embodiment, the guide device 200 may be devoid of the shoulder230 and as such, D₂ may be equal to or greater than D₁ to allow aclearance around a remaining portion of the guide device 200 andeffectively allow the drilling system 1 to descend into the ground.

Another practical advantage of the drilling system 1 is the ability totransform its configuration to be used as a drill bit or as an underreamer at will. For instance, in some cases, it may be desirable todrill a “socket” in the ground underneath the bottom end of the casing500 once it has reached a required depth in the ground (e.g. when thecasing 500 reaches a bedrock at a given depth in the ground). A socketmay be generally defined as a void (e.g. empty space) that may be filledwith concrete or other structural material (e.g. cement) to immobilizeor at least solidify the bottom end of the casing 500 in the ground.

The socket may have various sizes and shape. For instance, in thisembodiment, the socket may have a size that is no greater than (e.g.,equal to) D_(C1), In other embodiments, the socket may have a bore sizeat least as large as (i.e. as large as or larger than) the outerdiameter Dc2 of the casing 500.

The drilling system 1 may be used to drill the socket. For instance,once the casing 500 has reached a required depth in the ground, thedrilling system 1 may drill the socket in the first drillingconfiguration or in the second drilling configuration as discussedabove. In cases where a socket with a bore size larger than the outerdiameter Dc2 of the casing 500 is necessary, the drilling system mayfirst drill in the first drilling configuration until a given depth(e.g. 12 inches) deeper than the bottom end of the casing 500 isreached. Then, the wings 300 may be deployed in their extended position(e.g. in the rock or in the overburden), thereby allowing the drillingsystem 1 to drill in the second drilling configuration to complete thesocket with a bore size larger than the outer diameter Dc2 of the casing500.

Although the examples of operation discussed above expose a drillingsystem 1 engaged in a casing 500 to drill a hole and simultaneouslydrive down a casing in the hole being drilled, it is to be understoodthat the drilling system 1 of the present invention can work without thepresence of a casing 500 and/or abutment ring 510, i.e. the drillingsystem can be used to drill a hole without simultaneously driving acasing 500 down the hole. For instance, instead of using the abutmentring 510 of a casing 500 to lock and unlock the driver 100 from one ofthe locking positions and to retract or extend the wings 300, the guidedevice 200 may simply be in friction relationship with the ground, orotherwise, to maintain the guide device 200 stationary relative to thedriver 100.

With reference to FIGS. 39 to 56, there is shown another embodiment ofthe drilling system 1 according to the present invention. In thisembodiment, the drilling system 1, works similarly as discussed above.As such, the features of the drilling system 1 according to thisembodiment that are similar to features previously discussed withrespect to the drilling system 1 of the previously-presented embodimentwill not be further discussed, but for the differences that arediscussed below.

In this embodiment, the wing locking mechanism at the lowermost portionof the lower section 102 of the driver 100 includes three radialprojections 130 configured to interact with a notch 340 formed at aninner surface 320 of each of the wings 300. Each of the radialprojections 130 are configured to register in a corresponding notch 340on each one of the three wings 300. In this embodiment, the wing lockingmechanism has a different shape than as previously discussed. Moreparticularly, the lowermost portion of the lower section 102 of thedriver 100 includes an enlargement 134 that is configured to contact arear surface 372 of the wings 300 when the drilling system 1 is in thesecond drilling configuration (discussed above). As such, the winglocking mechanism may not serve only for locking the wings 300 in theretracted position, but may also provide an additional contact areabetween the driver 100 and the wings 300 while the drilling system 1 isin the second drilling configuration. This may help to furtherdistribute the drilling loads within the wings 300, the driver 100 andthe guide device 200 during drilling in this drilling configuration.

In this embodiment, the wings 300 have a slightly different shape asthat of the previously-presented embodiment. More particularly, asdiscussed above, each wing 300 includes a rear surface 372 at a lowerend thereof that is configured to contact the enlargement 134 of thedriver, as discussed above. Also, each wing 300 includes a bottomsurface 374 underneath that is configured to contact a bottom surface ofthe aperture 250 in the guide device 200. This feature of the wing mayhelp to further distribute drilling loads within the wings 300, thedriver 100 and the guide device 200 during drilling in the seconddrilling configuration.

In some variants, where an abutment ring 510 or a casing crown 520 isused with the drilling system 1, the abutment ring 510 or the casingcrown 520 may be configured to engage the wings 300 of the drillingsystem 1 when they are in their extended position, such as to preventthe guide device 200 from rotating relative to the driver 100 when theoperator desires to unlock the wings 300 from the second drillingconfiguration and retract them. For instance, as shown in FIGS. 57 and58 the abutment ring 510 and the casing crown 520 may include a seriesof recesses 524 on the circumference thereof that are configured tointerlock with the extended wings 300. Once the extended wings 300engage respective recesses on the casing crown 520 or abutment ring 510,the guide device 200 connected with the wings 300 is prevented fromrotating relative to the casing crown 520 or abutment ring 510, therebyfacilitating unlocking the bayonet connection of the driver 100 and theguide device 200, and in turn unlocking the drilling system 1 from thesecond drilling configuration.

Certain additional elements that may be needed for operation of someembodiments have not been described or illustrated as they are assumedto be within the purview of those of ordinary skill in the art.Moreover, certain embodiments may be free of, may lack and/or mayfunction without any element that is not specifically disclosed herein.

Any feature of any embodiment discussed herein may be combined with anyfeature of any other embodiment discussed herein in some examples ofimplementation.

In case of any discrepancy, inconsistency, or other difference betweenterms used herein and terms used in any document incorporated byreference herein, meanings of the terms used herein are to prevail andbe used.

Although various embodiments and examples have been presented, this wasfor the purpose of describing, but not limiting, the invention. Variousmodifications and enhancements will become apparent to those of ordinaryskill in the art and are within the scope of the invention, which isdefined by the appended claims.

The invention claimed is:
 1. A drilling system, comprising: a driver forconnection to a drilling rod configured to impart drilling action to thedriver, a guide device, at least one wing mounted to the guide device,the at least one wing capable to acquire an extended position toconfigure the drilling system to drill an extended diameter bore and aretracted position to configure the drilling system to drill a reduceddiameter bore, the driver and the guide device being coupled to eachother via a bayonet connection defining a plurality of engagementpositions, including a first engagement position in which the at leastone wing is in the extended position and a second engagement position inwhich the at least one wing is in the retracted position, in either oneof the first and second engagement positions the driver being configuredto communicate the drilling action imparted by the drilling rod to theguide device to drill a bore of a selected one of the extended orretracted diameter.
 2. A drilling system as defined in claim 1, whereinthe drilling action imparted by the drilling rod includes a rotationaldrilling motion.
 3. A drilling system as defined in claim 2, wherein thedrilling action includes a hammering action.
 4. A drilling system asdefined in claim 1, wherein the drilling system has a rotational axis,the first engagement position of the bayonet connection and the secondengagement position of the bayonet connection being spaced apart fromeach other about the rotational axis.
 5. A drilling system as defined inclaim 1, wherein the drilling system has a rotational axis, the driverbeing configured for moving about the rotational axis with relation tothe guide device to selectively engage or pull-out one of the engagementpositions.
 6. A drilling system as defined in claim 1, wherein thedriver and the guide device are configured in the first and in thesecond engagement positions to lock the at least one wing in theextended position and the retracted position, respectively.
 7. Adrilling system as defined in claim 1, wherein the drilling systemcomprises a plurality of wings.
 8. A drilling system as defined in claim7, wherein the wings are equispaced about a periphery of the guidedevice.
 9. A drilling system as defined in claim 1, wherein the at leastone wing includes a drilling face, in the first engagement position thedrilling face being extended outwardly from a periphery of the guidedevice to achieve the extended diameter bore, in the second engagementposition the drilling face being retracted relative to the position itacquires in the first engagement position to achieve the reduceddiameter bore.
 10. A drilling system as defined in claim 9, wherein theat least one wing moves pivotally between the extended position and theretracted position.
 11. A drilling system as defined in claim 10,wherein the driver is configured to engage the at least one wing to lockthe at least one wing in a selected one of the extended position andretracted position.
 12. A wing configured for use with the drillingsystem as defined in claim
 1. 13. A guide device configured for use withthe drilling system as defined in claim
 1. 14. A driver configured foruse with the drilling system as defined in claim
 1. 15. A drillingsystem as defined in claim 1, wherein the driver is configured to causedisplacement of the at least one wing from the extended position to theretracted position when the driver pulls out of the first engagementposition and acquires the second engagement position.